Respiratory mask



FIG. 1 is a front perspective view of a frame for a respiratory maskaccording to our new ornamental design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a right side view thereof, with the left side view thereofbeing a mirror image thereof; and,

FIG. 7 is a rear perspective view thereof.

The broken lines illustrate unclaimed environment or structure and donot form a part of the claimed design.

CLAIM The ornamental design for a respiratory mask, as shown anddescribed.